Process for dyeing articles produced from aromatic polycarbonates



United States Patent Int. Cl. D06p 3/54 US. Cl. 8-4 6 Claims ABSTRACT OF THE DISCLOSURE Dyed aromatic polycarbonate articles with a dispersion or developing dyestuff and a process for effecting said dyed articles comprising impregnating the articles with a dye composition containing an effective amount of at least one of an alkoxyalkylbenzyl ether, alkylene glycoldi-benzyl ether, benzoic acid alkoxyalkyl ester, or phenoxy acetic acid-alkoxyalkyl ester.

The present invention relates to a process for the dyeing of articles produced from aromatic polycarbonates with dispersion or developing dyestuffs. The process consists in carrying out the dyeing in the presence of a compound of the formula in which R represents an alkyl radical, or a benzyl or phenyl radical which may be substituted in the aromatic nucleus by alkyl and/or halogen, R means hydrogen or an alkyl radical, and R is a benzyl, benzoyl or phenoxyacetal radical which may be substituted in the aromatic nucleus by alkyl and/ or halogen, and n is a number from 2 to 4.

Examples of the compounds of the Formula I inelude the following: ethyl-glycol-benzyl ether, butylglycol-benzyl ether, butyl-gylcol-p-chlorobenzyl ether, butyl glycol trichlorobenzyl ether, ethyleneglycol-dibenzyl ether, propyleneglycol-1,2-dibenzyl-ether, propyleneglycol 1,3-dibenzyl-ether, butyleneglycol-1,4-dibenzylether, 2-phenoxyethyl-benzyl-ether, benzoic acid-Z-ethoxyethyl ester, benzoic acid-Z-butoxyethyl-ester, p-chlorobenzoic acid 2-butoxyethyl-ester, benzoic acid-2-benzyloXyethyl-ester, benzoic acid-2-phenoxyethyl-ester, phenoxyacetic acid-2-ethoxyethyl-ester, phenoxyacetic acid-2- benzyloxyethyl-ester, phenoxyacetic acid-Z-phenoxyethylester.

In accordance with the present invention, it is possible to effect a dyeing of articles, e.g. filaments, fibres, fabrics and foils, produced from aromatic polycarbonates by means of dispersion or developing dyestuffs yielding deep shades, while substantially accelerating the dyestuff absorption.

The necessary amounts of the compounds of the Formula I to be used according to the invention can be readily determined in each case by preliminary experiments; in general, amounts of 0.2 to 4 g. per litre dyeing liquor are found to be sufficient depending upon the desired depth of colour of the final dyeing and the liquorto-goods ratio.

Since the compounds of the Formula I are water-insoluble, care must be taken that they are present in the dyebath in an emulsified form; for this purpose they can be added in the form of solutions in organic solvents, e.g. in isopropyl alcohol, to the dyebaths which contain an emulsifier or an emulsifier mixture; however, it is also ice possible to proceed in such a manner that mixtures which are prepared from the compounds of the Formula I and emulsifiers are added to the dyebaths. Anion-active and/ or non-ionic compounds are preferably used as emulsifier.

In the present case, there are to be understood by the term aromatic polycarbonates, preferably those polycarbonates which are based on dihydric phenols. Dihydric phenols comprise, for example, hydroquinone, resorcinol, dihydroxy-diphenyl, but chiefly bisphenols, such as bis- (hydroxyphenyl)-alkanes, e.g. 2,2-bis-(4-hydroxyphenyl)- propane (bisphenol A), bis-(hydroxyphenyl)-cycloalk anes, -ethers, -sulphides, -sulphoxides or -sulphones, and mixtures of such dihydric phenols.

Suitable dispersion and developing dyestuffs are, for example, those described in Diserens, Die neuesten Fortschritte in der Anwendung der Farbstolfe, 2nd volume, 2nd edition (1949), pages 254 et seq., and 1st volume, 2nd edition (1946) pages 304 et seq.

The parts given in the following examples are parts by weight.

EXAMPLE 1 Fibres of bisphenol A-polycarbonate =1.75 to 2.15 in methylene chloride, c.=0.5 g./ ml. at 25 C.) are introduced into an aqueous bath having a liquor-to-goods ratio of 40:1 and containing, per litre, 0.75 g. of the dispersion dyestufii 1-hydroxy-(p-tolyamino)-anthraquinone and 2 g. sodium salt of N-oleyl-N-methyl-taurine. 2.5 grams 2-butoxyethyl-benZyl-ether, dissolved in isopropyl alcohol, are then added, per litre, to the bath while stirring. The fibres are subsequently dyed at 96-98 C. for 2 hours, then rinsed and dried. A deep blue dyeing of very good fastness to light is obtained.

Deep blue dyeings of very good fastness are also obtained,'i f 2-butoxyethyl-benZyl-ether is replaced by one of the following compounds: 2-ethoxyethyl-benzyl-ether, 2 propoxy ethyl-benzyl-ether, 2-phenoxyethyl-benzylether, propylene glycol 1,2 dibenzyl-ether, butyleneglycol 1,3-dibenzyl-ether, benzoic acid-2-propoxyethylester, benzoic acid-2-benzyloxy-ethyl-ester, benzoic acid-2- phenoxyethyi ester, phenoxyacetic acid 2-ethoxyethylester, phenoxyacetic acid 2-butoxyethyl-ester, phenoxyacetic acid-2-benzyloxyethyl-ester, phenoxyacetic acid-2- phenoxyethyl-ester.

When the procedure is followed as described above, but with the difference that there are added to the hot dyebath, instead of 2.5 g. 2-butoxyethyl-benzyl-ether, 5 g. of a mixture which is prepared from 50 parts ethyleneglycol-dibenzyl-ether, 35 parts water, 9 parts of the monoethanol ammonium salt of tetrapropylene-benzene-sulphonic acid and 6 parts of the reaction product of 16 mols ethylene oxide with 1 mol. o-benzylphenol, or of 25 parts 2-butoxyethylbenZyl-ether, 25 parts benzoic acid-2-butoxyethyl-ester, 35 parts of water, 9 parts of the mono ethanol-ammonium salt of tetrapropylene-benzene-sulphonic acid and 6 parts of the reaction product of 16 mols ethylene oxide with 1 mol o-benzyl-phenyl-phenol, a deep blue dyeing of very good fastness to light is also obtained.

EXAMPLE 2 Polycarbonate fibres of the type described in Example 1 are introduced into an aqueous bath having a liquorto-goods ratio 40:1 and containing, per litre, 0.75 g. of the dispersion dyestutf 1 amino 4-hydroxy-2-bromoanthraquinone and 3 g. sodium dinaphthyl-methane-disulphonate. 2.5 grams benzoic acid-2-ethoxyethyl-ester, dissolved in isopropyl alcohol, are then added, per litre, to the bath, while stirring. The fibres are subsequently dyed at 9698 C. for two hours, then rinsed and dried. A

3 deep red dyeing of very good fastness to light is obtained.

We claim:

1. A process for dyeing aromatic polycarbonate articles with a dispersion or developing dyestuff, comprising impregnating the articles With a dye composition containing an effective amount of an additive of the formula in which R is alkyl, benzyl, phenyl or the corresponding substituted radicals wherein the substituents are members selected from the group consisting of alkyl and halo; R is hydrogen or alkyl; R is benzyl, benzoyl, phenoxyacetyl or the corresponding substituted radicals wherein the substituents are members selected from the group consisting of alkyl and halo; and n is an integer of 2-4.

2. The process of claim 1 comprising effecting the dyeing in the presence of an alkoxyalkylbenzyl ether or the corresponding chloro substituted components having as substituent in the aromatic nucleus at least one halo radical.

3. The process of claim 1 comprising effecting the dyeing in the presence of an alkyleneglycol-dibenzyl ether or corresponding substituted compounds having as substituent in the aromatic nucleus at least one halo radical.

4. The process of claim 1 comprising effecting the dyeing in the presence of 'a benzoic acid alkoxyalkyl ester or corresponding substituted compounds having a substituent in the aromatic nucleus at least one halo radical.

5. The process of claim 1 comprising effecting the dyeing in the presence of a phenoxy acetic acid-alkoxyalkyl ester or corresponding substituted compounds having as substituent in the aromatic nucleus at least one halo atom radical.

6. The dyed polycarbonate obtained according to claim 1.

References Cited UNITED STATES PATENTS 3,003,843 10/1961 Amick 8-93 X 3,189,641 6/1965 Brack et al. 8173 X 3,385,652 5/1968 Walter et al. 84

GEORGE F. LESMES, Primary Examiner T. I. HERBERT, JR., Assistant Examiner US. Cl. X.R. 

